1. Field of the Invention
The present invention relates to an ultrasound endoscope and an ultrasound balloon for an endoscope and, more particularly, to an ultrasound endoscope and an ultrasound balloon for an endoscope in which a balloon is easily detached from a distal end portion of an insertion portion.
2. Description of the Related Art
Conventionally, an ultrasound endoscope has been widely used in a medical field and the like. The ultrasound endoscope obtains ultrasound data through transmission and reception of ultrasound between a distal end portion of an insertion portion and a test target and generates an ultrasound image. A doctor or the like can diagnose the test target in a noninvasive manner looking at the ultrasound image.
In the ultrasound endoscope, an ultrasound probe portion for transmitting and receiving ultrasound is provided at the distal end portion of the insertion portion. In the ultrasound endoscope, a balloon for interposing liquid, for example, water, which is an ultrasound medium for transmitting ultrasound, between an observation target of a subject and the ultrasound probe portion is attached to the distal end portion of the insertion portion. After use of the ultrasound endoscope, the balloon is detached from the distal end portion of the insertion portion.
Conventionally, various proposals concerning balloons of ultrasound endoscopes have been made. Japanese Patent Application Laid-Open Publication No. H07-227393 proposes a technique for, when attaching a balloon to a distal end portion of an insertion portion of an ultrasound endoscope, facilitating the attachment by eliminating a part where air escapes in a storage bag portion.
Japanese Patent Application Laid-Open Publication No. H07-155326 proposes a balloon device for an ultrasound probe that prevents air from being mixed in an inside when an ultrasound transmission medium is encapsulated in a balloon main body.